Serum leptin, insulin resistance, and body fat after renal transplantation.
OBJECTIVE
Our objective was to evaluate serum levels of leptin, body mass index (BMI), body-fat percentage (BF%), and insulin resistance in the first year after renal transplantation.


METHODS
This study involved a prospective, observational cohort.


METHODS
The setting was a transplant unit of a university teaching hospital in Porto Alegre, Brazil.


METHODS
Thirty-two patients who underwent renal transplantation were prospectively followed for 1 year. A control group of 19 healthy individuals, matched by sex, age, and BMI, was included in the study.


METHODS
Body mass index and BF% were measured according to anthropometric measures, serum leptin was measured by radioimmunoassay, and the homeostasis model assessment (HOMA) was used as an index of insulin resistance. Anthropometric measures and biochemical markers were evaluated prospectively, starting at transplant time and then every 3 months for up to 1 year.


RESULTS
Leptin levels were increased before transplantation, and decreased significantly in the first year (median, 11.9 [interquartile range, 9.2 to 25.2] to 9.3 [4.9 to 16.4] ng/mL; P < .001). The HOMA values presented a similar pattern, decreasing from 2.4 +/- 1.5 (mean +/- SD) before transplantation, to 1.5 +/- 1.1 (P = .001) at 3 months after transplantation, but increasing to 2.0 +/- 1.7 at month 12 after transplantation (P = not significant). The BMI and BF% increased significantly in the first year after transplantation (23.3 +/- 2.7 kg/m(2) vs. 24.4 +/- 2.7 kg/m(2), P = .001, and 23.71% +/- 7.79% vs. 25.63% +/- 7.68%, P = .002, respectively). According to multivariate regression analysis, HOMA levels and BF% independently predicted leptin levels after transplantation.


CONCLUSIONS
We found that leptin serum levels decreased significantly over the first posttransplant year. However, the effect of transplantation on insulin resistance appears to be transitory, and BF% also increases steadily in this period. The beneficial profile of leptin levels is counterbalanced by the detrimental effects of insulin resistance and BF% that may be related to the elevated cardiovascular risk observed after transplantation.
Souza
Gabriela Corrêa
GC
Division of Nephrology, Hospital de Clínicas de Porto Alegre, Rio Grande do Sul, Brazil.
Costa
César
C
Scalco
Rosana
R
Gonçalves
Luiz Felipe
LF
Manfro
Roberto Ceratti
RC
D000273:Adipose Tissue / Q000378:metabolism*; D050154:Adiposity / Q000502:physiology; D000328:Adult; D001823:Body Composition / Q000502:physiology*; D015992:Body Mass Index; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007333:Insulin Resistance; D007676:Kidney Failure, Chronic / Q000628:therapy; D016030:Kidney Transplantation; D020738:Leptin / Q000097:blood*; D008297:Male; D011446:Prospective Studies
D020738:Leptin